Antoine Jean Baptist Vaillant was an artist at thé Museum d'Histoire Naturelle in Paris. He illustrated numerus zoological works. Among the herpetological works he illustrated were the turtles and crocodiles in Auguste Dumeril's (1852-1856) Description des Reptiles nouveaux ou imparfaitement connus de la collection du Museum d'Histoire Naturelle and Alphonse Guichenot (1850) Reptiles et poissons. Exploration scientifique de l'Algérie pendant les années 1840-1842.
This original water color is of Daboia mauritanica (Dumeril & Bibron, 1848) is from Guichenot's Algeria work. It is interesting to note the overall lack of detail in this watercolor. There is a small section of the neck with scales drawn in and a small section of just the scale detail separate from the snake. I didn't scan the back of this watercolor, but it has several pencil sketches, mostly of mollusks.
The final (published) version of this plate in Guichenot is also illustrated here. You can see the much greater detail with the entire body covered with scales. There are also two illustrations of the head which were not included on the watercolor, but were presumably drawn elsewhere. It would be interesting to know how much Vaillant oversaw the engraving. This plate includes credit to Visto sculps (the engraver), this was J. P. Visto (Vistau) and N. Remond imp. (the printer).
Apparently the plate was printed in 1848, two years before the official publication date of 1850. Dumeril and Bibron wrote their description in 1848 and Gray cites their description in his synonymy of Clotho? mauritanica, causing a bit of confusion for a while since Gray's description was published before Dumeril and Bibron's description that he cited. Today Dumeril and Bibron are credited with the original description. (see the Reptile Database: http://reptile-database.reptarium.cz/species?genus=Daboia&species=mauritanica)
For more images of A.J.B. Vaillant's published illustrations see: http://www.photo.rmn.fr/C.aspx?VP3=SearchResult&VBID=2CO5PCU49K8R#/SearchResult&VBID=2CO5PCU49JYQ